Modular air diffuser



M 2 1 61 J. A. ROBERTS 2, 82,1 7

ay 9 MODULAR AIR DIFFUSER Filed Sept. 12, 1958 2 Sheets-Sheet 1 mum I WINVENTOR. chmss ,4. ossers May 2, 1961 J. A. ROBERTS MODULAR AIRDIFFUSER V 2 Sheets-Sheet 2 INVENTOR. Jams: A @0552]! w 4% v UnitedStates Patent MODULAR AIR DIFFUSER James A. Roberts, 1907 Lorene St.,Whittier, Calif. Filed Sept. 12, 1958, Ser. No. 760,638 4 2 Claims. (Cl.98-40) This invention relates to devices for controlling the flow of airinto a room or like enclosure, and more particularly to an improvedlouvered diifuser apparatus for selectively directing and controllingair flow.

Louvered air diffusers of the prior art are generally designed to effectthe flow of air into a room in different directions. However, in none ofthese is it possible to selectively control, at the diffuser, both theeffective area and the volume of air flow therethrough into a desiredpart of the room.

Some diffusers have no movable elements, and therefore no means'tocontrol the effective area of air flowing from a duct to which thediffuser is attached, and the only way in which the volume of airflowing into the room can be controlled with such diffusers is to varythe pressure of air flowing through the duct.

Most louvered air diffusers are equipped with movable bafiles or vanesto be used in conjunction with fixed louvers, such vanes being movablesimultaneously to equally restrict or enlarge the areas through whichair flows in different directions therethrough. Thus, although this typeof diifuser provides means for controlling the eifective neck or throatarea, it is not possible with such structures to control air flow sothat the volume of air entering a room in one direction is differentfrom that entering the room in another direction.

With the movable vane diffusers of the prior art, the

volume of air directed to different parts of the room is substantiallythe same. In mounting such a diffuser, the conventional procedure is tolocate the diifuser so that air flow into the room is relatively welldistributed. However, and as is well known, there are many factors'whichprevent the selected setting for the vanes from being much better than acompromise. Such factorsinclude the size and placement of walls,windows, fireplaces, doorways and furnishings.

In many situations, it can readily be determined that for maximumcomfort in all parts of a room,'the volume and thrust of air in thedifferent parts of the room will differ. However, with the prior artdiffusers, the best that can be accomplished is to adjust the movablevanes to provide what appears to be relatively satisfactory distributionof air in two or three directions, and let that sufiice. In theremaining direction or directions, the room is almost always too hot ortoo cold, depending upon the setting of the vanes.

It is an object of this invention to provide an improved louvered airdiffuserof a movable vane type, wherein the vanes are individuallyadjustable, and wherein the adjustment of vanes associated with louversoriented in a particular direction eifects accurate control of both theeffective area and the volume of air flow through the louvers in thatdirection.

Another object of this invention is to provide an improved diffuserstructure having separate modules or cores, each including fixed louversand movable damper or vane elements, wherein the modules and the vanesare adapted to be positioned to control the direction of air ICCcomponent parts of simple design, capable of being readily assembled andadjusted to effect distribution of air for optimum comfort in all partsof a room.

It is still another object of this invention to provide im proved aircontrol means suitable for directing the flow of air into a room, andwhich has selectively adjustable elements for permitting the diffuser tobe adjusted at the site of installation'to effect distribution of airfor maximum comfort in all parts of the room.

The above and other objects and advantages of'this invention will becomeapparent from the following description, taken in conjunction with theaccompanying drawings illustrating a preferred embodiment thereof, andin which:

Figure 1 is a perspective view of a ceiling air diffuser having modulespositioned for directing air into a room in four directions;

Figure 2 is an enlarged sectional view taken along the line 22 of Figure1, showing the arrangement of individual' bafiles'or vanes forselectively controlling the effective area in a module;

Figure 3 is a fragmentary sectional view taken along the line 3--3 ofFigure 2, showing how the modules are fitted into their surroundingframes;

Figure 4 is a fragmentary sectional view taken along the line 44 ofFigure 2, showing how the vanes are pivotally mounted;

Figures 5-9 are schematic diagrams of different arrangements of fourmodules to show how they can be oriented and utilized to control boththe effective area and the volume of air flow in different directionstherethrough; Figure 10 is a schematic diagram of a rectangular array offour modules, to illustrate the adaptability of the modular constructionof this invention to different forms;

Figure 11 is a schematic diagram illustrating a diffuser employing twomodules for directing air from a corner 7 into the interior of a room;and

Figure 12 is an exploded view of the parts of the diffuser of Figure 1,showing clearly how the parts fit within each other.

Referring to the drawings, a ceiling air diffuser 10 is provided with anouter frame 11 which fits into the ceiling, indicated at 12 in Figure l.The frame 11 has a square central shell 14 which extends into a ductopening 15 (see Figure 2) in the ceiling 12. The lower edge of the shell14 terminates in an outwardly flaring square brim 16 which slopesdownwardly, as indicated 7 at 17, and which is turned up at its edges,as at 18, so

as to abut the ceiling 12.

Snugly fitted within the outer shell 14 is an inner frame 20, disposedat the same angle as the sloping section 17 of the frame 11. Preferably,and as shown, the

sloping portion 17 is shaped, as by crimping, so that the portionthereof adjacent the lower edge of the shell 14 is offset from theremaining portion thereof by the thickness of the flared portion 17' ofthe frame 20. In this manner, the outer surfaces of the portion 17' and'17 are coterminous, so as to provide a smooth surface. The portion 17of the frame 20 is secured to the portion 17, as by metal screws 21.

Supported within the frame 2% are four cores or modules 2'5, 26, 27 and28- (see Figure 12) each con- 3 The louvers are fixed within respectivesquare frames 30, 31, 32 and 33 which, upon being placed together, fitsnugly within the square frame 20.

As illustrated, the louvers of each section face in the same direction.Their slopes are the same, and such is also the slope of the portions17, 17 of the respective frames 11 and 20. Thus, for each moduleillustrated in Figure 1, there are four equal openings through which aircan pass from the duct 15.

Preferably, the shells 30, 31, 32 and 33 can be assembled on the frame20 with their louvers facing in any one of four directions. As shown inFigure 1, these shells are oriented so that they can direct air in fourdirections. However, and as illustrated by the arrows in Figures 9 toindicate the direction in which the louvers are pointed, the shells maybe oriented to effect diffusion of air into the room, in three or twodirections, or even in one direction.

In order that the shells 30, 31, 32 and 33 can each be positioned withinthe frame 20 so that their louvers are oriented in a desired one of fourdirections, each such shell is exactly the same. size and shape. Eachside of each shell is provided with two spaced openings 40 at its upperedge (see Figure 12) so that when the shell is inserted in a corner ofthe frame 20, the openings 40 on adjacent sides thereof are aligned withcorresponding openings 41 on adjacent sides of the frame 26. After theshells are thus assembled on the frame 20, elongated bolts 42 (seeFigure 2) are passed through the aligned openings in the frame 20 andthe shells. The bolts 42 are threaded at one end, where a respective nut43 is secured to tighten the shells within the frame 2%).

In each shell, a respective vane element is provided adjacent eachlouver for adjusting the area through which air can flow. Since the vaneand louver construction for each of the modules is the same, thefollowing description will be directed to the construction within one ofthe shells 30, which is illustrated in Figures 2 and 4.

As shown, each of the louvers 25 includes a vertical portion 25" whichis secured, as by welding, to the shell 30. Forward of each verticalsection 25" is a respective vane element 45 which is pivotally mountedon the shell 30, as on pins 46 secured to opposite sides of the shell.Limit stop projections 48 are provided on the shell 30 below the pins 46to limit clockwise movement of the vanes 45 beyond the point where thevane is substantially in a vertical position. The width of each vane 45is such that it can be moved counterclockwise to a point where itsopposite edges abut adjacent louvers, as indicated in phantom line inFigure 2, to close off the air passages therebetween. Furthermore, thevanes are all in the open position on mounting the structure in place.Thereafter, a simple rod tool is thrust from the front of the structureand pressed against the lower edge of a vane to be closed; pushing onthe vane causes it to rotate to the closed position. Pressing on a vaneto move it to the closed position is necessary to overcome thefrictional on the ends 46. Such friction is, of course, the reason forcewhich holds the vane in the open position, such friction beingestablished by the frictional fit of the vane the vane remains in anyposition to which it is forced.

In order to understand how the above described structure controls thevolume (i.e., cubic feet per minute) and the effective area throughwhich air flows in any direction, its operation will be describedqualitatively, as for a frictionless structure, and somewhatover-simplified. Assume that air at a give npressure flows through theduct 15, and that the vanes in all the modules are in the open position.In such an arrangement, it will be seen that the effective area of eachmodule is the same, that the volume of air (i.e., cubic feet per minute)flowing through each module is one-fourth of the total, and that thethrust of air through each module is the same.

If two of the vanes 45 in one module 25 are placed in the closedposition, the effective throat area ofthat module is reduced one half.However, the volume of air flowing through the module 25 is alsoreduced. This will readily be understood when it is considered that thetotal volume of air must now flow through fourteen small areas ratherthan the sixteen small areas (four per module), that were availablebefore the two vanes 45 were closed.

With all the vanes open, one-sixteenth of the total volume flows througheach small throat area, whereby four-sixteenths, or one-fourth, of thetotal volume flows through each module. When the two vanes 45 of themodule 25 are closed, leaving the fourteen small throat areas,one-fourteenth of the total volume of air flows through each small area.Accordingly, four-fourteenths, or two-sevenths, of the total volumeflows through each of the modules 26, 27 and 28, and two-fourteenths, orone-seventh, of the total volume flows through the module 25.

Thus, it will be seen that upon closing two of the vanes 45 of themodule 25, the throat area is reduced by one-half, and the volume of airflowing therethrough is reduced from one-fourth to one-seventh.Simultaneously, the volume of air flowing through the remaining modules26, 27 and 28 is increased from one-fourth to tWo-sevenths, althoughtheir total effective areas remain the same.

In another arrangement wherein the four modules are oriented indifferent directions (see Figure 8) one module 25 has all of its vanes45 in the open position, a second module 26 has two vanes in the closedposition, as indicated at 50, a third module 27 has one vane in theclosed position, as indicated at 51, and the fourth module 28 has threeof its vanes in the closed position, as indicated at 52. Thus, thisarrangement provides ten small throat areas through which the air canflow (four in the module 25, two in the module 26, three in the module27, and one in the module 28). Therefore, one-tenth of the total volumeflows through each small throat area, with the result that $6 or 6, ofthe total volume flows through the module dr Me, of the total volumeflows through the module cif the total volume flows through the module27; f d f the total volume flows through the module 28.

Thus, although the effective throat areas of the module 25 remain thesame, the total volume flowing therethrough is increased from one-fourthto two-fifths, over the arrangement wherein the vanes of all the modulesare in the open position. Reducing the throat area of the module 26 byone-half results in a reduction of volume flow from one-fourth toone-fifth. However, although the throat area of the module 27 is reducedto three-fourths of its maximum, the volume of air flow therethrough isincreased from one-fourth to three-tenths. Finally, the reduction of theeffective area of the module 28 to onefourth of its maximum causes thevolume of air flow therethrough to be reduced from one-fourth toonetenth.

In Figure 5, the modules 25, 27 and 28 are shown oriented to direct airin one direction, and the module 26 is oriented to direct air in theopposite direction. With all of the vanes open, it is apparent thatthree-fourths of the total volume will flow in the direction in whichthe modules 25, 27 and 28 are oriented, and the remaining one-fourthwill flow in the direction in which the module 26 is oriented. However,with two vanes of the module 26 in the closed position, as indicated at53, thereby reducing its effective throat area by one-half, only oneseventh of the total volume will flow in the direction in which it isoriented. Meanwhile, although the effective throat area of the modules25, 27 and 28 remains the same, the total volume of flow in thatdirection is increased from three-fourths to six-sevenths.

In Figure 6, the modules25' and28 are oriented to direct air in onedirection, and the modules 26 and 27 are oriented to direct air in theopposite direction. As indicated at 54 and 55, one vane in each of themodules 26 and 27 is in a closed position. Thus, each of the modules 26and 27 has its effective throat area reduced by one-fourth, i.e.,. tothree-fourths of its maximum, while the effective throatareas. ofmodules 25 and 28 remain the same. Whereas, with all the vanes. in theopen position, one-half of the total volume of air flow would bedirected in opposite directions, the, closure of one vane of each of themodules 26 and 27 results in sixfourteenths, or three-sevenths, of thetotal volume flowing in the direction in which they are oriented, andthe total.

volume flowing in the direction in which the modules 25 and 28 areoriented is increased to four-sevenths.

In Figure 7, the modules are oriented to direct air in three directions.In this arrangement, the module 25 is oriented to direct air in onedirection, and has all of its vanes in the open position. The module 26is oriented to direct air in the direction opposite to that flowingthrough the module 25, and all of its vanes are in the open position..The remaining modules 27 and 28 are oriented to direct. air in adirection at right angles to that flowing from each of the modules 25and 26. Additionally, two of the vanes of the'module 27 are in theclosed position, and one of the vanes of the'module 28 is in the closedposition, as indicated respectively at 56 and 57. Thus, the area of themodule 28 is reduced to threefourths of its maximum. The net result isthat fourthirteenths of the total volume of air flowsthrough each of themodules 25 and 26, whereas two-thirteenths of the total volume flowsthrough the module 27, and threethirteenths flows through the module 28.Therefore, this arrangement results in reducing the total eifective areathrough which air flows in the direction of orientation of the modules27 and 28 to five-eights of its maximum, and reduces the total volume ofair flow in that direction from one-half to five-thirteenths. Meanwhile,although the efiective throat areas on modules 25 and 26 remain thesame, the air flow therethrough is increased from one-fourth tofour-thirteenths.

Figure 9 shows an arrangement wherein all of the vanes of module 26 arein the closed position, as indicated at 59, with all of the vanes in theremaining modules 26, 27 and 28 being in the open position. Further, thetwo modules 25 and 28 are oriented to direct air at right anglesthereto. Whereas, with the vanes of the module 26 in the open position,one-fourth of the air volume would flow through the module 27, andone-half of the volume would be directed, through the modules 25 and 28,closing off the module 26 results in the total volume being dividedamong the twelve small throat areas. Thus, although the effective throatarea of the module 27 remains the same, the total volume of air flowtherethrough y is increased from one-fourth to one-third.Simultaneously, although the effective throat areas of the modules 25and 28 remain the same, the air flow therethrough constitutes two-thirdsof the total volume instead of onehalf.

This invention is not limited to a square configuration for a diffuser;nor is it limited to modules having only four louvers each. For example,and referring to Figure 10, four modules 60, 61, 62 and 63 are shownplaced side by side in a rectangular configuration. Further, each isprovided 'with five louvers. As shown, each of the modules is orientedto direct air in a respective direction. With the vanes of all themodules in the open position, it is apparent that one-fourth of thetotal volume will flow in the respective directions. As with the modularconstruction above described, the closing off of individual louversections of the modules, so as to reduce the effective throat area ofone or more of them, will operate to increase or decrease the volume ofair flow in the different directions.

Figure 11 illustrates an arrangement oi'tWo modules 65 and 66 fororienting air in directions, atright angles to each other, and which isuseful for a ceiling difiuser placed in the corner of a room. Such adual modular construction also permits selective controlof both throatarea and volume. For example, if two of the vane elements of one of themodules 66 were placed in the closed position, this would leave eightsmall sections through which the air would flow. Thus, three-eights ofthe total volume would flow through the module 66 and the remainingfive-eights would flow through the module 65. V i

As previously stated, the foregoing explanation of controls for volumeand area is oversimplified. Also to be taken into consideration is thethrow, in feet, from each module. Given a particular diffuser size andneck velocity, both the volume and throw in a given direction will haveto be determined.

For example, assume that one employs a 16" x 16" diffuser, having a neckarea of 1.78 sq. ft., and a neck velocity of 500 feet per minute. Thedifiuser has four '8" x 8" modules, each having eight vanes, andeachhaving one-fourth the above-mentioned neck area, i.e., 0.445 sq. ft.With the modules arranged to direct air in four directions, (a) one hasall vanes in the open position, (b) another has six vanes in the openposition, (0) a third has half its vanes in the open position, and (d)the fourth has only two vanes in the open position.

Measured volume and throw for the above-described arrangement was asfollows:

(a) 223 c.f.m. (0.445 sq. ft.) with a 7-foot throw. (b) 170 c.f.m.(0.333 sq. ft.) with a 6-foot throw. (0) c.f.m. (0.223 sq. ft.) with a4.9-foot throw. (d) 55 c.f.m. (0.11-1 sq. ft.) with a 35-foot throw.

Thus, although the area of the (d) diffuser is only onefourth that ofthe (a) diffuser, its throw is one-half that of the (a) diffuser.

The significance of the invention will now be apparent. For each of thedifferent directions of air flow, the volume and effective area for airflow in any direction are finely controlled. This is in sharp contrastto prior art registers of the type wherein individually adjustable vanesare located between deflector plates that are all parallel with the axisof the duct, and to prior art diffusers of the type employing modulesthat can only direct air at the same volume through effective throatareas that are all the same size. In the type of register that usesindividually adjustable vanes with stationary plates that are allparallel to the duct axis, substantially all air flows only in onedirection, i.e., parallel to the duct axis. Since this is so, adjustingits individual vanes provides nothng to aid in understanding what wouldbe the effect of adjusting individual vanes in louvered modules that areoriented to direct air in different directions. And since prior artdifiusers that use differently oriented louvered modules also areincapable of selectively controlling air flow in diiferent directions,it will be seen that my unique structure operates in a novel manner toobtain an end result of which prior art structures are incapable.

It will be seen from the foregoing description that this inventionprovides a unique modular core air difiuser in which throw and volumeare selectively controllable in any direction, by virtue of effectivearea control which can be adjusted in discrete increments from 0-100%.Diffusers made in accordance with this invention are quiet, and providea degree of comfort in all parts of a room which has hitherto beenimpossible to attain with prior art difiusers.

While the embodiment of my invention herein shown and describedillustrates the advantages of my invention, it will bereadily apparentthat many modifications can be made which do not depart from the spiritand scope of my invention. Therefore, I do not intend that my in-.

7 vention be limited to the particular embodiment herein shown anddescribed, except as defined in the appended claims.

I claim:

1. A diffuser for air'entering a room from an air duct comprising: a'shell to receive air from the air duct and having a rectangular airoutlet opening therein; a plurality of square frame members of the samesize; means releasably securing said frame members in edge abuttingrelationship within said air outlet opening, the number and size'of saidframemembers being such as to fill said outlet opening; a plurality ofparallel louver elements secured Within each frame member, each of saidlouver elements comprising an inner plate portion parallel to the axisof said air outlet opening and an outer air deflecting portion extendingat an acute angle to said axis, said frame members being capable ofdifferent angular orientations within said air outlet-openingcommensurate with the alignment of frame sides relative to the sides ofsaid opening to cause the outer air deflecting portions of the louverelements in the frame members to extend in different directions fromsaid axis; a plurality of baflle elements each positioned inwardly ofthe air deflecting portion and adjacent the inner plate portion of alouver element; means pivotally mounting each baffle element forindependent pivotal movement into and out of engagement with the innerplate portions of adjacent louver elements, said mounting meansincluding means retaining the bafiie elements in any position ofadjustment between limits of maximum and minimum air flow betweenadjacent louver elements, whereby the quantity of flow of airdirectionally issuing from the louvers of said frame members can becontrolled by selectively orienting the frame members to control thedirection in which the air deflecting portions of their respectivelouver elements extend from said axis and by individual manipulation ofthe respective bafile elements.

2. A diffuser as defined in claim 1 wherein said shell has a flangeextending at an acute angle to the axis of said outlet opening, saidacute angle being the same as that between said air deflecting louverportions and said outlet opening axis.

References Cited in the file of this patent UNITED STATES PATENTS1,217,225 Schueler Feb. 27, 1917' 2,116,873 Williams May 10, 19382,236,865 Bailey Apr. 1, 1941 2,300,049 Kurth Oct. 27, 1942 2,560,802Lambert July 17, 1951 2,564,334 Kennedy Aug. 14, 1951 2,792,985 HeimanMay 21, 1957 2,865,277 Howe Dec. 23, 1958

